Electron discharge device



'J ly 1934. F. HUNTER, JR

ELECTRON DISCHARGE DEVICE Filed Oct. 29, 1924 A Fig. v2.

Patented July 24, 1934 PATENT OFFICE ELECTRON DISCHARGE DEVICE Frederick L. Hunter, Jr.,

Towaco, N. 1., assignor,

by mesne assignments, to Radio Corporation of America, a corporation of Delaware Application October 29, 1924, Serial No. 746,617

This invention relates to electron discharge devices and more particularly to the means and method for flashing the said device. The objects of the invention are to enable a flashing material to be used which cannot be welded to the plate; to permit use of a flashing material which is in powder or lump formation; to associate said flashing material in close proximity to the plate so as to flash the same by heating the plate; to

provide a container for the flashing material; to

provide a container which is cheaply and readily manufactured, filled and closed; to provide a container which may be spot welded to the plate; to

provide for the escape of gases from the container as the same is heated and to promote rupture at a desired part of the container; to secure simplicity of construction and obtain an improved method of flashing electron discharge devices; and to obtain other advantages and results as may be brought out in the following description.

Referring to the accompanying drawing in which like numerals of reference indicate similar parts throughout the several views;

Fig. 1 is a view in elevation of an electron discharge device showing the invention mounted therein;

Fig. 2 is a face view of the plate of an electron discharge device showing thereon a container for so flashing material;

Fig. 3is a perspective view of said plate and container;

Fig. 4 is a sectional view on line 4-4 of Fig. 2; and

Fig. 5 is an enlarged sectional view of the container and a portion of the plate.

It has been a common procedure heretofore to weld a strip of magnesium to a plate in an electron discharge device before introducing the same into itsglass shell or housing, and subsequently flashing the magnesium by heating the plate in one way or another. The strip of magnesium can be very readily spot welded to the plate and is accordingly in close association therewith so as to flash readily when the plate is heated. There are, however, certain materials which obtain a reduction of residual gases more effectively than magnesium, but which are not of such form as to be readily welded to the plate. It has probably been for this reason that such materials have not been employed heretofore. The flashing material which I have in mind is in powder or lump formation, and the present invention involves the means and method of utilizing such a material as the flashing material for the electron discharge device. In carrying out the invention I employ a specially made container which will carry the flashing material and which is readily attached to the plate by welding or otherwise. In the specific embodiment of the o0 invention illustrated in said drawing, the reference numeral 1 indicates in general the electron discharge device having a base 2 and closed housing or glass shell 3 as is common in the art. Within the housing 3 is a stem 4 provided for 35 sealing-in the lead wires and supporting the working parts of the device, including a plate 5.

In the present disclosure said plate 5 is preferably rectangular, altho it is to be understood that the invention may be applied to plates having other shapes if so desired. Furthermore, as shown, the plate is provided with parallel spaced walls between which the usualgrid and filament (not shown) may be included. On the outside of opposite faces of the plate, as clearly shown in Fig. 4, are mounted containers 6. The exact position of these containers upon plate 5 may be varied, and I do not wish to be understood as limiting the invention to-placing said container at any particular place. However, it is preferable go to mount the said containers substantially opposite each other so both will be heated substantially to the same degree and the contents will then have a tendency to both flash at the same time.

The container is preferably stamped from a 35 single piece of material, the same being stamped or shaped'so as to provide a pocket 7 preferably semi-spherical, near'one end portion of the strip of material. This pocket is of an appropriate size and shape to receive the powder or lump 9o flashing material, and the other end of the strip is then doubled back so as to close over the open face of the pocket and thus enclose the flashing material. The doubling back of one end of the strip of material brings the two end portions of 9 said material flatwise together, and said end portions may be crimped, spot welded or otherwise prevented from separating if so desired, or the container" may be immediately applied to the plate and a single operation of spot welding employed for retaining the two end portions of. the strip material together and holding the container upon the plate.

Preferably there is a tiny hole or perforation 8 at the peak of the pocket, permitting escape of gas as the plate is heating, and at the same time, encouraging or causing rupture of the material at that part of the container when the contents of the pocket flash. It is desirable that the rupture be thus controlled so as to avoid any inJury no pocket, and having the other end thereof doubled over to lie flatwise against the first mentioned end and close said pocket.

2. A method of flashing electron discharge devices comprising inserting a perforated container in said device, said container having a flashing material therein, and subsequently heating the said container so as to cause said material to flash and rupture the container in the proximity of said perforation.

FREDERICK L. HUNI'ER, Ja. 

